DHCP Reservations

It is a Windows 2012 Server running DHCP passing out IPs in the range 192.168.1.100-254

I am having trouble making a reservation at 192.168.1.4. Is that because it doesn't fall in the range of 100-254?

Kind of a awkward question....
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LockDown32OwnerAsked:
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JohnBusiness Consultant (Owner)Commented:
A DHCP reservation is what it says and the reservation must fall within the DHCP scope. Change the IP to within the scope or use a Static IP address.

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LockDown32OwnerAuthor Commented:
Can the reservation fall in an exclude range?
JohnBusiness Consultant (Owner)Commented:
No. You must use the DHCP range for a DHCP reservation.

Or use a different approach of a Static IP.
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Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
A DHCP reservation outside of the DHCP range does not make sense. A reservation is intended to pin a DHCP IP address to a MAC address, after it has been allocated. Any address outside of the DHCP scope needs to be a static one.
Mal OsborneAlpha GeekCommented:
Odd, I have been creating DHCP reservations outside of the main pool for decades now. Works with NT 3.51, NT 4.00  Windows 2000, 2003, and 2008. I have never tried on a 2012 server, but I would be surprised if it differed.

This makes perfect sense; on the site where I am now sitting, workstations have IPs in a range from 192.168.10.100 - 192.168.10.199, a single pool doles them out. Printers are from 192.168.10-50 - 192.168.10.70, via reservations. All printers are runnig with reservations outside of the pool, but in the same subnet, as is required in the question.
Mal OsborneAlpha GeekCommented:
Hmm, the plot thickens!  

Here is an article claiming that this behaviour changed with Server 2008R2.
https://support.microsoft.com/en-us/help/2005980/you-cannot-add-a-dhcp-reservation-which-is-outside-of-the-scope-distribution-range-in-windows-server-2008-r2

I, however have a 2008R2 here server where this works just fine.
Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
Yes, you can add reservations outside of the DHCP scope. I've done that on 2008r2 too for exercising.

As said, doing that is nonsense. If you want to keep a record of used IP addresses, do so by using static DNS entries in case the devices don't register themselves (otherwise DNS is already up-to-date).
Using DHCP reservations require to enter the MAC address, and there is no link to a name - this combines useless info with the lack of useful info.
Mal OsborneAlpha GeekCommented:
The device name shows up when a DHCP lease becomes active, just like any DHCP lease.

Here is a screenshot. This is a Windows10 PC, targeting a 2008R2 server.

Capture.JPG
Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
Sorry, you are correct about the name, but still I would use that feature only in very rare cases.
LockDown32OwnerAuthor Commented:
That is why it was an awkward question. In thinking about it logically it could go either way. The Reservation is done by the DHCP Server but that doesn't necessarily equate to it having to be in the scope range. The reason is stupid anyway. A screw up by HPE on their 19XX and 16XX series switches. They put all these neat NTP features in but but forgot to put a place in the GUI to set  gateway address. Oops! The NTP works if you let it go DHCP but I like knowing where my switches are. Usually static IP them. Hence the shot at a reservation. HPE has been living off their name for way too long. Even if you look at the MAC Address (Unique ID) that the DHCP Server picks up it is always like 2341241295398723857989325768235525 and when you try to turn it in to a reservation it gives you the warning that the MAC address isn't standard and asks if you want to use it anyway. HPE says they can get a reservation to work. I can't. The only difference I can see is that my reservation is outside the scope. It works when it was inside the scope.
JohnBusiness Consultant (Owner)Commented:
If your IP address is outside the DHCP scope, why not just use a Static IP address. Yes, you need a small document to list the IP addresses you use, but it would solve your problem very well.
LockDown32OwnerAuthor Commented:
I love using static IP addresses. That is the way it should be but as mentioned above when I use a static IP address there is no place to put a gateway address and as a result none of the NTP functions work because without a gateway address the switch has no internet. I don't know what HPE was thinking. Obviously they weren't.....
Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
Seriously? You cannot put in a gateway with static IPs in those switches?
LockDown32OwnerAuthor Commented:
Yes. A total bonehead move. I opened a case with HPE a year ago and there response was "we are trying to make a low cost switch and had to omit that feature" yet they put stuff in for Daylight Savings, NTP and the rest. There are ways to do it:

On both the 1920 and 1620 you can use the console cable and set the gateway via the CLI but how inconvenient is that? Serial ports went out with mini skirts back in the 70s.

On the 1920 you can telnet to it and set it with the CLI or use a static route.

They had room to put in this real annoying captcha verification when you log in to the switch but didn't have the room to set a gateway address? Kind of like Symantec. They have been living off their name way too long. Maybe it is time to change things up.
Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
You should be able to change the DHCP range to the full network, then exclude the range up to 99, and then do a reservation.
LockDown32OwnerAuthor Commented:
For the record the Reservation outside the scope did work. I must have pulled an HPE when I tried it the first time. Something that document says shouldn't work in 2012 R2 but does. The actual MAC address is 356338612e333836342e346438342d566c616e2d696e7465726661636531 can you believe that? Maybe I did a type the first time.

   Rather then jumping through all these hoops it sure seems like the simple approach would be for them to add a place to set a gateway address in the GUI but what do I know? Thanks guys....
JohnBusiness Consultant (Owner)Commented:
Thank you and good luck here.
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